The present invention concerns the application of identification labels to objects of substantially cylindrical irregular shape, particularly to food products having such a shape, such as sausage meats--especially salami, sausages, "coppa" and the like--and some cheeses.
As known, at present this operation is carried out manually, by picking the adhesive label from an automatic distributor which also dampens the same, and by applying it around the object to be identified.
As food products are involved, the label should not be glued on the object, but only on itself, at its overlapping ends. However, it should adhere to the object enough to be prevented from easily slipping of. These are the reasons why, up to now, labels have always been applied exclusively by hand. In fact, for an automatic application of the label, many difficulties have to be overcome, deriving from the typical nature of the products to be labelled, and this has so far not been accomplished. It should in fact be noted that:
the real diameter of the object to be labelled can differ even to a significant extent from the nominal one; for instance, in the case of salami, if the nominal diameter is of 40 mm, the real diameter can vary between 35 and 45 mm approximately;
the average diameter at the two ends of the object to be labelled is generally different (especially in sausage meats and cheeses, which are often of conical shape);
the cross section of the object to be labelled is seldom circular; more frequently, it is vaguely elliptical and, often, it takes up very irregular shapes;
the real length of the object to be labelled can be quite different (up to 20% more or less) from the nominal length;
the longitudinal axis of the object to be labelled is seldom rectilinear; in fact, sausage meats and cheeses usually take up a curved banana shape;
the label should be applied so as to adhere to the object to be identified and automatically adapt itself to any protuberances of said object, without forcing it to take up more regular geometrical shapes (which would harm its preservation, where--as in most cases--fresh food products are involved).